题解 | 支付间隔平均值
支付间隔平均值
https://www.nowcoder.com/practice/847431ad931e45348eb1ab5657144c28
select cast(avg(abs(timestampdiff(second,ol.logtime,sl.logtime))) as SIGNED) gap from order_log ol join select_log sl on ol.order_id=sl.order_id
abs 取绝对值,avg函数后 结果会变浮点数,所有不能直接输出,也不能用round取整,要用cast函数转化为整数类型。